An allergy is a body’s hypersensitive response to a substance. A peanut allergy is a reaction that occurs when your body mistakenly identifies peanuts as harmful substances. When you eat peanuts or food containing peanuts, your immune system–the body’s natural defense system that fights infections and diseases–overreacts and can cause a serious, even life-threatening response.
A peanut allergy can be mild and simply cause hives or it can be serious enough to result in an anaphylactic reaction which requires immediate medical attention as it can be fatal. The Asthma and Allergy Foundation of America estimates that the majority of pediatric and adult food allergy patients have a peanut allergy. Prevalence among adults and children is similar (around 1%) but at least one study shows it to be on the rise in children.
Causes
Peanut allergy is caused by an immune system malfunction. Your immune system identifies peanuts as harmful triggering the production of immunoglobulin E (IgE) antibodies to neutralize the peanut protein (allergen). These IgE antibodies recognize when you eat peanuts and signal your immune system to release histamine and other chemicals into your bloodstream. Histamine and other body chemicals cause a range of allergic signs and symptoms.
Symptoms
Allergic reactions to peanuts usually occur within minutes after exposure, although reactions within an hour or so after ingestion are possible. The most serious and potentially deadly allergic reaction to peanuts is an anaphylactic response. Other serious signs and symptoms of an anaphylactic reaction include:
- Wheezing
- Rapid or weak pulse
- Blueness of your skin, including your lips and nail beds
- Diarrhea
- Nausea and vomiting
- Dizziness
- Loss of consciousness
Treatment
For a mild reaction, you may only need to take an antihistamine, such as diphenhydramine hydrochloride (Benadryl), to reduce your symptoms of a runny nose or itchy skin. If you have had a severe reaction previously, your doctor has probably prescribed a medication called epinephrine. Give yourself an antihistamine and the epinephrine shot. However, the only way to prevent an allergic reaction is to avoid peanuts and peanut proteins altogether.